Plesk 12.x / Linux :: Failed Upgrade Results In Inconsistent DB And Unfunctional Panel

After last night's attempt to upgrade one of our old plesk servers (10.0.1), on RHEL 5.5, we are left with unfunctional control panel.

Following the KB [URL] ...., we see:

1) no /usr/local/psa/version file exists currently.

2) mysql -uadmin -p`cat /etc/psa/.psa.shadow` -D psa -e 'select * from upgrade_history order by upgrade_date desc limit 1'
+---------------------+--------------------------------+------------+
| upgrade_date | version_info | db_version |
+---------------------+--------------------------------+------------+
| 2010-12-01 10:52:30 | 10.0.1 RedHat el5 109101029.17 | 01090 |
+---------------------+--------------------------------+------------+

as you see the plesk was OLD. No line for the last night's upgrade, though in here.

3) but: rpm -q psa
psa-12.0.18-rhel5.build1200140606.15

So, the installation procedure finished partially, installing net packages, but not really updating all info.

Comparison of the MySQL scheme for DB psa with another server with the new installation shows that some minimal differences in some tables and a couple of missing tables. So, it looks like it _almost_ succeeded.

Comparison of the RPMs installed on the two servers, shows some differences in installed packages and versions. For example, there are 2 versions of psa-backup-manager and 2 versions of psa-migration-manager on the "malfunctioning" machine.

Further runs of the autoinstaller does not work, since it seems to think that everything is fully installed/updated. How to proceed from this point. Control panel does not work...

We've looked through the installation log files and Wonder if there is some log file that we are missing - where shold we look for messages in case of a failed installation?